This invention relates in general to sound amplification and more particularly to coupling and mounting arrangements for sonic transducers feeding signals to audio amplifiers.
The mounting of sonic transducers on radiating surfaces for sound pick up and amplification purposes is generally well known whether it be for medical reasons on human beings, for reproduction of musical tones, for sonic testing materials, or for measurement of fluid flow in conduits. The use of suction cup devices to removably hold a transducer on a radiating surface is also well known as disclosed, for example, in U.S. Pat. No. 2,752,914 to Pohlman and U.S. Pat. No. 3,496,297 to Brumberger. Further, the use of elastomeric material to hold the transducer in spaced relation to the radiating surface as part of a sonic coupling arrangement is disclosed in each of U.S. Pat. Nos. 3,394,586 and 4,279,167 to Cross and Erb et al, respectively. According to both of the latter two patents, the sonic transducer is mounted within a recess or cavity formed in the coupling body, the entire coupling body being made of elastomeric material in the case of the Cross patent.
The foregoing prior art includes use of sonic coupling and mounting arrangements for transducers on the radiating surface of a musical instrument as the sound generating device in order to faithfully amplify and reproduce musical tones. For such installations, the use of a condenser microphone type of transducer has been proposed because of its known characteristics. However, the use of a condenser microphone type of transducer for such purpose requires a source of electrical voltage as well as output voltage control. The mounting of such transducers in one assembly with its associated circuitry, controls and battery power source as an independent portable unit, is also known as disclosed in U.S. Pat. No. 3,305,638 to Teachout. However, because of the mounting of such transducer directly on the radiating surface of a sound generator and the desire to avoid disturbing the sensitivity of the transducer, the voltage source and control was deemed to be most logically located remote from the transducer to which it would be coupled by conductors of suitable length.